Add an exception test to check for memory leak for vector(n, x, a)

Author: winner245

libcxx/test/std/containers/sequences/vector/vector.cons/exceptions.pass.cpp

@@ -139,6 +139,14 @@ int main(int, char**) {
   check_new_delete_called();
 #endif  // TEST_STD_VER >= 14
 
+	try { // Throw in vector(size_type, value_type, const allocator_type&) from the type
+		int throw_after = 1;
+		ThrowingT v(throw_after); 
+    std::vector<ThrowingT> vec(1, v, std::allocator<ThrowingT>());
+  } catch (int) {
+  }
+  check_new_delete_called();
+
   try { // Throw in vector(InputIterator, InputIterator) from input iterator
     std::vector<int> vec((Iterator<std::input_iterator_tag>()), Iterator<std::input_iterator_tag>(2));
   } catch (int) {